The latest in this popular series is in a larger format that generously accommodates an outdoor setting and a new character: a puppy who joins canine babysitter Carl and his small human charge on the merry-go-round, digging in a flower bed, sharing an ice cream, calling at the zoo, etc.; the original duo even poses for a painting club whose members represent them in several recognizable styles. The dogs are as charmingly true to life as ever, while the fantasy will beguile fans and worry a few literal-minded caregivers. (Picture book. 3-8)